Crow’s feet Botox overdone: why, how long and what to do

Crow’s feet are the small fan-shaped lines that appear at the corners of the eyes when you smile. After an injection, the corner of the eye sometimes barely moves at all: your eyes no longer "smile" while your mouth does. This situation is one of the problems around the eyes after a botulinum toxin injection. It is bothersome from an aesthetic point of view, harmless for the eye in most cases, and temporary. This page answers the seven questions people ask most often.

Why do crow’s feet look overdone?

Crow’s feet are caused by the orbicularis oculi muscle, a ring-shaped muscle that surrounds the eye and is used to close the eyelids and to crinkle the eyes. To soften them, the toxin is injected into this muscle, outside the eye socket^1,2. When the relaxation achieved is stronger than intended, the corner of the eye no longer crinkles at all and the expression of the eyes changes.

This relaxation can have other consequences, described in a review of upper face complications⁴:

• the lower eyelid may look laxer and the bags more visible, because the muscle holds back the fat pads less well;
• in people whose lower eyelid is already lax, an injection too close to the edge of the eyelid can make it pull slightly away from the eye (ectropion);
• strong relaxation of the muscle can prevent the eye from closing fully and encourage dryness.

Finally, the smile itself can change. The labels recommend avoiding injections too close to the zygomaticus major muscle, which lifts the corner of the mouth¹, and injecting outside the eye socket, away from the muscle that lifts the eyelid². The review specifies that injections should not be placed too low: reaching this muscle can alter the tone of the upper lip and create an asymmetry⁴.

How soon after the injection does it appear?

The effect appears as the toxin starts to work. After treatment of crow’s feet with a type A toxin, improvement of the lines is seen from the first 6 days, with the peak effect around day 30¹. Your eyes may therefore look increasingly frozen over the first few weeks.

How long does it last?

As long as the effect of the product injected. For crow’s feet, one type A toxin showed an effect on lines for up to 5 months in trials². The effect fades gradually: the corner of the eye regains its mobility little by little. The page on how long botulinum toxin lasts explains durations of effect product by product.

The short-acting botulinum toxin (serotype E) is not approved for crow’s feet: it is approved only for frown lines³.

Is it reversible?

Yes. The block of the muscle by botulinum toxin is temporary: new nerve sprouts form, then the original nerve endings resume their function⁵. The orbicularis muscle then regains its strength and the eyes their usual expression.

Is there a treatment?

No product reverses the effect of botulinum toxin: you wait for the muscle to regain its mobility. What can be treated are some of the consequences. If the eye does not close properly or becomes dry, lubricating eye drops and gels are recommended⁴; the page on dry eyes explains these measures. If the lower eyelid pulls away from the eye, a medical opinion, possibly from an ophthalmologist, is needed.

For the next session, the doctor can adapt the dose and injection points: the review cited stresses adapting the points to each person’s line pattern, observed during a forced smile, and taking precautions when the lower eyelid is lax⁴.

What should you avoid?

Do not ask for another injection to "get back" the smile in your eyes: the toxin relaxes muscles, it cannot give them back their strength. Do not shorten the interval between sessions: the label of a type A toxin states that intervals between two treatments should not be shorter than 3 months¹. Do not rub your eyes if they become dry, and do not use any eye drops other than a lubricant without medical advice.

When should you see a doctor?

Talk to the doctor who performed the injection if the result bothers you, so that they can take it into account next time. See a doctor sooner if you cannot close your eye fully, if the eye becomes red, painful or very dry, if the lower eyelid pulls away from the eye, or if your vision is blurred or double: reduced blinking, reported with botulinum toxins, can lead to dryness and damage to the cornea³.

Related pages describe the other possible effects of an injection at the corners of the eyes: dry eyes, puffy eyelids and the asymmetric smile, when the toxin reaches the smile muscles.